Combustion and/or heating apparatus

ABSTRACT

A burner having a combustion zone with means for directing a combustion supporting material into the zone in counter-rotating streams.

United States Patent Van Grecken [451 Oct. 8, 1974 COMBUSTION AND/OR HEATING APPARATUS Inventor: Gene Van Grecken, Sydney,

Australia Assigneez' Gvang Motor Company Pty.

Limited, Brookvale, New South Wales, Australia Filed: Feb. 26, 1973 Appl. No.: 335,915

Foreign Application Priority Data Mar. 20, 1972 Australia 40174/72 US. Cl 431/182, 239/400, 239/404,

, 239/427.3, 239/433 Int. Cl. F23m 9/00 Field of Search 431/173, 182, 185, 188,

[56] References Cited UNITED STATES PATENTS 1,910,735 5/1933 Zikesch 239/400 3,179,150 4/1965 Arnold 431/173 3,361,366 1/1968 De La Foumiere 431/353 3,539,284 11/1970 Wolfersperger 431/173 3,671,173 6/1972 Guerre et a1 431/182 Primary Examiner-Kenneth W. Sprague Attorney, Agent, or Firm-Robert E. Wickersham 5 7] ABSTRACT A burner having a combustion zone with means for directing a combustion supporting material into the zone in counter-rotating streams.

13 Claims, 10 Drawing Figures PATENTEUUCT 8l974 3,840.328

SHEET 10F 5 PATENTEDUBT 8 I374 SHEET 30F 5 WTER SHEET t 0F 5 PATENTEDUBT 8 I974 M \HT 6 WW Q: a V 1 w @0 0 000.0M0gw0000 .00000000000%w Wm wIIPJ O O OO O QQQQQQQQQQQQQ 0 000000 0 @0000 w M w W w 0 g 0 m 00000000000000660000 0 000000 M w a n "w 8 5 s if u s 5 lm JV M 0 a M 00000000mM00000000000 m o 0 mWo -00 Wm m. 9 r|v\ 6 m 0 wow mm 0 3 000 000000000000 00 0000000: 00000 m 9 x m 5 0 000000o oowog ooooooooooooowwm 0 Q w w A COMBUSTION AND/OR HEATING APPARATUS This invention relates to a combustion apparatus and, in particular, to a burner, which may, for example, be used with a steam generator.

The burner in accordance with the present invention may comprise a combustion zone, a fuel delivery nozzle or jet located at one end of the combustion zone, and at least one pair of channels extending about the combustion zone, the respective channels being in fluid passage communication with the combustion zone and the channels of the or each pair being disposed about the combustion zone in opposite senses whereby a combustion supporting fluid directed through the two channels will enter the combustion zone in counterrotating streams.

The respective channels are preferably formed as volutes, the channels being mounted one to the other(s) to form a single unit, and the channels preferably have a common (inner) wall which defines the combustion zone.

The fluid passage communication between the respective channels and the combustion zone is preferably arranged in such manner that the fluid streams enter the combustion zone in spaced relationship, the stream entry being spaced apart in the direction of fuel propagation from the delivery nozzle or jet.

In one preferred form the burner comprises two said channels only, the channels communicating with the combustion zone through slots formed in the wall defining the combustion zone and the slots associated with the respective channels being spaced apart in the direction of fuel propagation by a generally cup-shaped member which is located within the combustion zone. The cup-shaped member is formed with an aperture in the base thereof, the aperture being in axial alignment with the fuel delivery nozzle or jet.

The fuel delivery nozzle or jet is preferably mounted to a support base which, in turn, supports the channels and combustion zone defined thereby.

The burner in accordance with the present invention may be employed for various purposes including, for example, the firing of gas or liquid fuels in furnaces. However, whilst it may have various applications the burner has been developed primarily for employment in conjunction with a novel form of steam generator.

The invention in its various forms will be more fully understood from the following description of a preferred embodiment thereof taken in conjunction with the accompanying drawing wherein:

FIG. 1 is a perspective view, from one end, of a burner assembly according to the invention FIG. 2 is an elevation view of the burner FIG. 3 is a view similar to that of FIG. 2 with portions of the burner casing cut-away FIG. 4 is a perspective illustration of the burner when viewed in the opposite direction from that of FIG. 1

FIG. 5 is a full sectional elevation view of the burner taken along plane 5-5 of FIG. 4

FIG. 6 is a perspective view of a steam generator having a burner of the invention shown mounted (in dotted outline) to one end thereof and having a portion of its wall cut-away,

FIG. 7 is a sectional elevation view of the steam generator taken along plane 7-7 of FIG. 6,

FIG. 8 is a schematic diagram of water/steam flow paths through the steam generator; and

FIGS. 9 and 10 are plan and elevation views respectively of a typical heating tube for location in the steam generator- Referring firstly to the burner ,as specifically illustrated in FIGS. 1 to 5; it comprises a support base 20 having a recessed upper surface fitted with a liquid fuel atomizing nozzle 21. The atomizing nozzle extends into and is in fluid passage communication with a diametral fuel delivery port 22, the port being screwed at each of its ends for connection with a fuel delivery line 23.

A combustion zone 24, which is defined generally by a cylindrical wall 25, is located ahead of the atomizing nozzle 21. The combustion zone is located within two surrounding channels 26 and 27, and the channels are mounted as a unit to the support base 20 by bolts 28.

The two channels 26 and 27 are in the form of volutes and they each define a generally rectangular section passage 29 of reducing cross-sectional area. Thus, the two channels have a (common) inner annular wall constituted by the cylindrical wall 25 of the combustion zone, an outer spiral form wall 30, a planar end wall 31 and a helical form end wall 32.

Also, the two 'voluted channels 26 and 27 are mounted one upon the other in inverted relationship and in such manner that they spiral in opposite senses about the combustion zone 24, the helical form end wall 32 constituting aninte'rmediate wall of the two channels.

The inner end 33 of the respective channels 26and 27 is closed, but the outer (larger) end 34 of each channel is open for receiving air which is'to be channelled into the combustion zone 24. The outer ends-34 of the channels are located adjacent one another and they terminate in a common flanged area 35.

A blower, not shown, would normally be mounted directly to the flange 35, for delivering air under pressure into each of the channels, the air. being divided into two streams having counter-spiralling within the channels.

The respective channels 26 and 27 communicate with the combustion zone 24 through slots 36 and 37 which are formed in the combustion zone wall 25. The slots 36 and 37 are spaced-apart in the axial direction of fuel-propagation from the atomizing nozzle 21 and they do, but for a narrow bridging piece 38, extend around the circumference of the combustion zone wall. Thus, with this construction, air conveyed through the respective channels 26 and 27 will be delivered into the combustion zone in counter-rotating streams, as shown by the'arrows in FIGS. 3 and 5.

A stationary cup-shaped member 39 is located within the combustion zone 24, it being in peripheral contact with the combustion zone wall 25 and being located axially between the two slots 36 and 37. The base portion 40 'of the member 39 is apertured at 41 in axial alignment with the atomizing nozzle 21. Also, the base portion 40 is connected with the combustion zone wall by an annular bridging member 40a.

In operation of the burner as above described, a liquid fuel is delivered to the nozzle 21 from which it is sprayed in a diverging stream of fine particles. A combustion supporting air stream entering the combustion zone 24 through the slot 37 entrains the fuel spray and resulting turbulence causes breakage of the fuel particles into yet finer particles. The resultant fuel/air mixture then passes through the cup aperture 41 where it directions meets with the second (counter-rotating) air stream entering through slot 36. Further turbulence then ensues to result in greater dispersion and particulation of the fuel.

Ignition of the fuel/air mixture is effected in operation of the device by a spark igniter 42 which is supported within the base 20 of the burner.

It will be appreciated from the foregoing that, while the zone 24 is referred to herein as a combustion zone (i.e. a zone in which combustion might be effected), the zone 24 is basically one in which mixing of a combustible fuel and a combustion supporting fluid is effected. Thus, it is to be understood that the actual flame of combustion resulting from ignition of the fuelfluid mixture need not necessarily be confined to the combustion zone, but that it may extend outwardly from such zone to enter a combustion chamber of an ancillary apparatus. The expression combustion zone is therefore to be read and understood in this context.

Reference is now made to FIGS. 6 to of the drawings, these illustrating a steam generator to which the above described burner is fitted. The burner is shown in dotted outline and indicated by numeral 50.

The generator incorporates a housing 51 composed of two half-cylindrical shells 52 and caps 53,54. The end cap 53 is formed with an integral tubular spigot 55 which enters the housing to define a combustion chamber 56, and the end cap 54 is formed with a similar spigot 57 which enters the other end of the housing to define an exhaust gas passage 58.

The housing components are formed from Inconel sheet material and, although not so shown, they would normally be lagged with an insulating material.

First and second heating zones 59 and 60 are disposed within and at opposite ends of the housing, they being separated by an intermediate disc-shaped partition 61. The partition member is formed as a laminate structure having two sheets of Inconel separated by a layer of Kaowool insulation.

The combustion chamber 56 enters into the first heating zone 59 and the exhaust gas passage 58 opens from the second heating zone 60. Thus, combustion of fuel from the burner 50 occurs in the combustion chamber 56 and the resulting gasses pass into the first heating zone 59. From such zone the gasses flow into the second heating zone 60 (following a path to be hereinafter described), then into the passage 58 from which they are exhausted through asuitable conduit to atmosphere.

Two water-steam heating tubes 62, 63 and 64, 65 are located within the respective heating zones, tubes 62, 63 being located concentrically about the combustion chamber 56 and tubes 64,65 being located concentrically about the exhaust gas passage 58.

The heating tubes 62 and 64 are both formed with a helically wound cylindrical portion and an integral spirally wound flange portion, this being most clearly illustrated in FIGS. 9 and 10. The tubes 63 and 65 are both formed in generally the shape of a bucket having a helically wound cylindrical portion and a spirally wound base portion.

A further, helically wound heating tube 66 of cylindrical form is located concentrically about the abovementioned heating tubes. The further heating'tube 66 extends between and into the two heating zones 59 and and it is located within a gas passage 67 which interconnnects the two zones.

Adjacent convolution of the respective heating tubes 62-66 are welded one to the other, in the interest of avoiding mechanical vibrations, and longitudinally extending spacer bars 68 which locate within the housing shells 52 are welded to the outer periphery of the further heating tube 66.

Barriers 69 arepositioned within the generator in order to deflect gas flow from the combustion chamber 56 through the heating zones and into the exhaust passage .58 in the general directions indicated by the arrows in FIG. 7.

The heating tubes 62,63,64 and are each formed throughout their entirety from a single length of conduit 70 (FIGS. 9 and 10). Thus, the conduit is formed in a spiral/helix configuration with successive convolutions 71, 72 of the configuration being arranged to carry a single column of fluid therethrough in mutually opposite directions, as indicated by the arrows in FIGS. 9 and 10.

This configuration is achieved by commencing winding of the tube in a central S-bend 73 and by winding two convolutions simultaneously, commencing with the two ends of the S-bend. Then, as shown in FIG. 9, the two free ends of the heating tube will extend from one end of the configuration. This in turn permits the convenient interconnection of the respectiveheating tubes shown in FIGS. 7 and 8.

Thus, the connection is from tube 64 to tube 65, from tube 65 to the lower end of the furthertconventionally wound) tube 66, from the upper end of tube 66 to tube tion is then made to the free end of tube 64, and a steam outlet connection is made'to tube 62. I

The actualheating tube layout and connection configuration, together with the water/steam flow pattern is illustrated schematically in FIG. 8 of the drawings. I claim: I '1. A burner comprising a wall defining a combustion zone, a fuel delivery nozzle located at one end of the combustion zone, a pair of tubular section volute form channels extending about the combustion zone in opposite senses-for directing a combustion supporting material into said combustion zone in counter-rotating streams, a cup-shaped member located within the wall defining the combustion zone, the cup-shaped member having a base portion formed with an aperture which is in axial alignment with the fuel delivery nozzle, and fluid passage communication zones extending through the wall defining the combustion zone from the respective channels, the respective fluid passage communication zones being spaced apart in an axial direction of fuel propagation from the nozzle and being located at opposite ends of the cup-shaped member.

2. A burner comprising a combustion zone,a fuel delivery nozzle or jet located at one end of the combustion zone, and at least one pair of channels extending about the combustion zone, the respective channels being in fluid passage'communication with the combustion zone and the channels of the or each pair being disposed about the combustion zone in opposite senses whereby a combustion supporting fluid directed through the two channels will enter the combustion zone in counter-rotating streams, said respective channels being in the form of tubular section volutes, the

channels having a common, inner, cylindrical wall constituting a wall which defines the combustion zone.

3. A burner as claimed in claim 2 wherein each channel has an outer spiral form wall, a planar end wall and a helical form end wall.

4. A burner as claimed in claim 3 incorporating two only said channels, the channels being mounted one upon the other in inverted relationship and in such manner that they spiral in opposite senses about the combustion zone.

5. A burner as claimed in claim 4 wherein the two channels share a common said helical form end wall.

6. A burner as claimed in claim 4 wherein the fluid passage communication zones between the two channels and the combustion zone are spaced-apart in the axial direction of fuel propagation from the nozzle or jet, the respective fluid passage communication zones being in the form of slots which extend circumferentially around the wall defining the combustion zone.

7. A burner as claimed in claim 6 wherein there is a stationary cup-shaped member located in peripheral engagement with the wall defining the combustion zone and axially between the fluid passage slots, the cupshaped member having a base portion formed with an aperture which is in axial alignment with the fuel delivery nozzle or jet.

8. A burner as claimed in claim 1 wherein the fuel delivery nozzle is mounted to a support base, the base in turn supporting the channels and the combustion zone defined thereby.

9. A burner as claimed in claim 8 including a fuel ignition device mounted to the support base and extending into the combustion zone.

10. A burner as claimed in claim 2 wherein the respective channels have an outer, open, end terminating in a common flange mounting.

11. A burner as claimed in claim 1 wherein the channels are defined by a common, inner, wall, said inner wall being constituted by the wall defining the combustion zone, and wherein each channel has an outer spiral form wall, a planar end wall and a common helical form intermediate wall, the two channels being mounted one upon the other in inverted relationship and in such manner that they spiral in opposite senses about the combustion zone.

12. A burner as claimed in claim 1 wherein the fluid passage communication zones are in the form of slots which extend in a circumferential direction around the wall defining the combustion zone.

l3. A-burner as claimed in claim 1 wherein the respective channels have an outer, open, end terminating in a common mounting flange. 

1. A burner comprising a wall defining a combustion zone, a fuel delivery nozzle located at one end of the combustion zone, a pair of tubular section volute form channels extending about the combustion zone in opposite senses for directing a combustion supporting material into said combustion zone in counter-rotating streams, a cup-shaped member located within the wall defining the combustion zone, the cup-shaped member having a base portion formed with an aperture which is in axial alignment with the fuel delivery nozzle, and fluid passage communication zones extending through the wall defining the combustion zone from the respective channels, the respective fluid passage communication zones being spaced apart in an axial direction of fuel propagation from the nozzle and being located at opposite ends of the cup-shaped member.
 2. A burner comprising a combustion zone, a fuel delivery nozzle or jet located at one end of the combustion zone, and at least one pair of channels extending about the combustion zone, the respective channels being in fluid passage communication with the combustion zone and the channels of the or each pair being disposed about the combustion zone in opposite senses whereby a combustion supporting fluid directed through the two channels will enter the combustion zone in counter-rotating streams, said respective channels being in the form of tubular section volutes, the channels having a common, inner, cylindrical wall constituting a wall which defines the combustion zone.
 3. A burner as claimed in claim 2 wherein each channel has an outer spiral form wall, a planar end wall and a helical form end wall.
 4. A burner as claimed in claim 3 incorporating two only said channels, the channels being mounted one upon the other in inverted relationship and in such manner that they spiral in opposite senses about the combustion zone.
 5. A burner as claimed in claim 4 wherein the two channels share a common said helical form end wall.
 6. A burner as claimed in claim 4 wherein the fluid passage communication zones between the two channels and the combustion zone are spaced-apart in the axial direction of fuel propagation from the nozzle or jet, the respective fluid passage communication zones being in the form of slots which extend circumferentially around the wall defining the combustion zone.
 7. A burner as claimed in claim 6 wherein there is a stationary cup-shaped member located in peripheral engagement with the wall defining the combustion zone and axially between the fluid passage slots, the cup-shaped member having a base portion formed with an aperture which is in axial alignment with the fuel delivery nozzle or jet.
 8. A burner as claimed in claim 1 wherein the fuel delivery nozzle is mounted to a support base, the base in turn supporting the channels and the combustion zone defined thereby.
 9. A burner as claimed in claim 8 including a fuel ignition device mounted to the support base and extending into the combustion zone.
 10. A burner as claimed in claim 2 wherein the respective channels have an outer, open, end terminating in a common flange mounting.
 11. A burner as claimed in claim 1 wherein the channels are defined by a common, inner, wall, said inner wall being constituted by the wall defining the combustion zone, and wherein each channel has an outEr spiral form wall, a planar end wall and a common helical form intermediate wall, the two channels being mounted one upon the other in inverted relationship and in such manner that they spiral in opposite senses about the combustion zone.
 12. A burner as claimed in claim 1 wherein the fluid passage communication zones are in the form of slots which extend in a circumferential direction around the wall defining the combustion zone.
 13. A burner as claimed in claim 1 wherein the respective channels have an outer, open, end terminating in a common mounting flange. 